San Francisco 49ers rookie running back Trey Sermon is a surprise inactive for Week 1 against the Detroit Lions.

Here's the full list of 49ers inactives for the season opener:

Sermon is a healthy scratch despite being the No. 2 running back on the depth chart, so this move comes out of nowhere:

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Raheem Mostert is the starting running back for San Francisco, so one has to imagine he's in line for a big game agains a bad Lions team. Fantasy football players who have Mostert rostered should be salivating at this matchup for him, especially with Sermon out. The 49ers also have JaMycal Hasty and Elijah Mitchell at running back.

San Francisco is trying to return to glory after a down 2020 season. After reaching the Super Bowl and losing to the Chiefs, the 49ers dealt with a number of injury issues in 2020 and went 6-10. They then traded up from No. 12 to No. 3 and took Trey Lance to be their quarterback of the future. Sermon went in the third round out of Ohio State.

Jimmy Garoppolo is still under center for right now, but Lance could see some action and will likely be the starter before long. The 49ers have a great opportunity to start the season right against Jared Goff an the Lions.